Sorting List using custom sorting technique
How to sort custom Objects using Bubble Sort ? (Example:1)
package com.gs.corejava.collections;
interface MyComparable<T> {
int myCompareTo(T object);
}
class Doctor implements MyComparable<Doctor> {
private int id;
private int age;
private String name;
/**
* @param id
* @param age
* @param name
*/
public Doctor(int id, int age, String name) {
super();
this.id = id;
this.age = age;
this.name = name;
}
/**
* @return the id
*/
public int getId() {
return id;
}
/**
* @param id
* the id to set
*/
public void setId(int id) {
this.id = id;
}
/**
* @return the age
*/
public int getAge() {
return age;
}
/**
* @param age
* the age to set
*/
public void setAge(int age) {
this.age = age;
}
/**
* @return the name
*/
public String getName() {
return name;
}
/**
* @param name
* the name to set
*/
public void setName(String name) {
this.name = name;
}
/*
* (non-Javadoc)
*
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Doctor [id=" + id + ", age=" + age + ", name=" + name + "]";
}
@Override
public int myCompareTo(Doctor doctor) {
if (this.getId() - doctor.getId() == 0) {
return this.getAge() - doctor.getAge();
} else {
return this.getId() - doctor.getId();
}
}
}
class MyCollections {
/**
* @param <T>
* @param arr
*/
public static <T extends MyComparable<T>> void bubbleSort(T[] arr) {
T c;
for (int i = 0; i < arr.length; i++) {
for (int j = 0; j < arr.length - i - 1; j++) {
if (arr[j].myCompareTo(arr[j + 1]) >= 0) {
c = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = c;
}
}
}
}
}
public class BubbleSort {
public static void main(String[] args) {
Doctor doctor = new Doctor(1, 65, "Mohit");
Doctor doctor1 = new Doctor(4, 26, "Rohit");
Doctor doctor2 = new Doctor(2, 23, "Amit");
Doctor doctor3 = new Doctor(6, 45, "Sumit");
Doctor doctor4 = new Doctor(2, 21, "Pooja");
Doctor[] doctors = { doctor, doctor1, doctor2, doctor3, doctor4 };
MyCollections.bubbleSort(doctors);
for (int i = 0; i < doctors.length; i++) {
System.out.println(doctors[i]);
}
}
}
Doctor [id=1, age=65, name=Mohit]
Doctor [id=2, age=21, name=Pooja]
Doctor [id=2, age=23, name=Amit]
Doctor [id=4, age=26, name=Rohit]
Doctor [id=6, age=45, name=Sumit]Example 2:
package com.tcs.hdfc.bancs.arraylist;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
interface MyComaparable<T> {
public int myCompareTo(T obj);
}
// class User implements MyComaparable<User> {
// private int id;
// private String name;
// private int age;
//
// public User(int id, String name, int age) {
// this.id = id;
// this.name = name;
// this.age = age;
// }
//
// public int getId() {
// return id;
// }
//
// public void setId(int id) {
// this.id = id;
// }
//
// public String getName() {
// return name;
// }
//
// public void setName(String name) {
// this.name = name;
// }
//
// public int getAge() {
// return age;
// }
//
// public void setAge(int age) {
// this.age = age;
// }
//
// @Override
// public String toString() {
// return "User [id=" + id + ", name=" + name + ", age=" + age + "]";
// }
//
// public boolean equals(Object obj) {
// boolean isSame = false;
// if (obj instanceof User) {
// User user = (User) obj;
// if (this.id == user.id && this.age == user.age &&
// this.name.equals(user.name)) {
// isSame = true;
// }
// }
// return isSame;
// }
//
// // public int myCompareTo(User obj) {
// //
// // if (this.getAge() < obj.getAge()) {
// // return 1; // +ve
// // } else if (this.getAge() == obj.getAge()) {
// //
// // if (this.getId() < obj.getId()) {
// // return 1;
// // } else if (this.getId() == obj.getId()) {
// // return 0;
// // } else {
// // return -1;
// // }
// //
// // } else {
// // return -1; // -ve
// // }
// // }
// public int myCompareTo(User obj) {
// return this.getAge() - obj.getAge() == 0 ? this.getId() - obj.getId() :
// this.getAge() - obj.getAge();
// }
//
// }
class User implements Comparable<User> {
private int id;
private String name;
private int age;
public User(int id, String name, int age) {
this.id = id;
this.name = name;
this.age = age;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "User [id=" + id + ", name=" + name + ", age=" + age + "]";
}
public boolean equals(Object obj) {
boolean isSame = false;
if (obj instanceof User) {
User user = (User) obj;
if (this.id == user.id && this.age == user.age && this.name.equals(user.name)) {
isSame = true;
}
}
return isSame;
}
// public int myCompareTo(User obj) {
//
// if (this.getAge() < obj.getAge()) {
// return 1; // +ve
// } else if (this.getAge() == obj.getAge()) {
//
// if (this.getId() < obj.getId()) {
// return 1;
// } else if (this.getId() == obj.getId()) {
// return 0;
// } else {
// return -1;
// }
//
// } else {
// return -1; // -ve
// }
// }
public int compareTo(User o) {
return this.getAge() - o.getAge();
}
}
public class ArrayListEx1 {
// public static void modifiedBubbleSort(List<User> users) {
//
// for (int j = 0; j < users.size(); j++) {
// for (int i = 0; i < users.size() - 1 - j; i++) {
// if (users.get(i).myCompareTo(users.get(i + 1)) > 0) {
// User temp = users.get(i);
// users.set(i, users.get(i + 1));
// users.set(i + 1, temp);
// }
// }
//
// }
// }
public static void bubbleSort(List<User> users) {
for (int j = 0; j < users.size(); j++) {
for (int i = 0; i < users.size() - 1 - j; i++) {
if (users.get(i).getAge() > users.get(i + 1).getAge()) {
User temp = users.get(i);
users.set(i, users.get(i + 1));
users.set(i + 1, temp);
}
}
}
}
public static void main(String[] args) {
List<User> users = new ArrayList<>();
User user1 = new User(1, "abcd", 23);
User user2 = new User(44, "abdd", 24);
User user3 = new User(8, "name3", 23);
User user4 = new User(78, "name4", 34);
User user5 = new User(35, "name5", 67); // 1019
users.add(user3);
users.add(user2);
users.add(user1);
users.add(user4);
users.add(user5);
User user55 = new User(5, "name5", 67); // 10190
System.out.println(users);
// will this fun remove
users.remove(user55);
System.out.println(users);
if (user5.equals(user55)) {
System.out.println("same");
} else {
System.out.println("diff");
}
// modifiedBubbleSort(users);
Collections.sort(users);
System.out.println(users);
}
}
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